This specification generally relates to search engines.
As the amount of information available on the Internet has dramatically expanded, users have had an increasingly difficult time formulating effective search queries for locating specific, relevant information. In recent years, competition among search engine providers has caused an explosive acceleration in the evolution of search engine algorithms, as well as in the user interfaces that are used to receive queries and display search results.
Various mechanisms can be used to provide queries to a search engine. For example, a user may type a query term into a search box using a keyboard on a computing device, and may then submit the query terms to a search engine. A user may implicitly define a query by panning around a map in order to obtain annotations for points of interest that exist on the displayed portion of the map. In addition, users may speak query terms into a microphone when using mobile devices (e.g., smartphones, music players, or tablet computers) that have small or virtual keyboards.